Wired circuit board and production method thereof

An elongated wired circuit board including a plurality of wires arranged in parallel,

• wherein the plurality of wires each includes
• a first linear portion extending in a first linear direction,
• a second linear portion having the same width as that of the first linear portion, disposed at one side in the first linear direction of the first linear portion, and extending in a second linear direction so as to have a predetermined angle θ relative to the first linear portion, and
• a connection portion disposed between the first linear portion and the second linear portion, being continuous with the first linear portion and the second linear portion, and having a width narrower than that of the first linear portion,
• the connection portion includes
• a first side further extending from a first widthwise one end edge orthogonal to the first linear direction of the first linear portion along the first linear direction,
• a second side further extending from the second widthwise other and edge orthogonal to the second linear direction of the second linear portion along the second linear direction, and
• the second linear portion includes
• a third side connecting the first side with the second widthwise one end edge of the second linear portion, and extending along the first-crossing direction crossing the first linear direction and the second linear direction, and
• the first linear portion includes
• a fourth side connecting the second side with the first widthwise other end edge of the first linear portion, and extending along the second-crossing direction crossing the first linear direction and the second linear direction,
• length y2 and length W satisfy the relationship of 0<y2<W,
• the length y2 extending from a second corner portion formed with the first widthwise one end edge of the second linear portion and the third side and reaching the first side along the first width direction, and
• the length W being the first width of the first linear portion, and
• the predetermined angle θ satisfy the relationship of
• 0<θ<1 deg.

A method for producing an elongated wired circuit board including a plurality of wires arranged in parallel, the method including the steps of:

• a first step, in which an insulating layer is prepared,
• a second step, in which the plurality of wires arranged in parallel are formed on the surface of the insulating layer, wherein
• the second step includes
• a step (1), in which a metal thin film is formed on the surface of the insulating layer,
• a step (2), in which a photo resist is formed on the surface of the metal thin film,
• a step (3), in which a photomask is disposed on the surface of the photo resist so as to face the photo resist, the photomask having a light transmission portion formed as a plurality of linear patterns arranged in parallel so as to match the plurality of the wires, and the photo resist is exposed to light through the photomask, and
• a step (4), in which the photo resist facing the light transmission portion is removed to expose the metal thin film,
• a step (5), in which the plurality of wires are formed on the surface of the exposed metal thin film by plating, and
• a step (6), in which the remaining photo resist, and the metal thin film facing the remaining photo resist are removed,
• wherein
• the second step includes a step of conducting the step (3) a plurality of times so that a connection portion having a width broader than a linear pattern is formed in each wire by shifting the photomask relative to the photo resist in the elongated direction, and
• in the each step of the plurality of steps, the photomask is disposed so that the linear pattern of the light transmission portion of the following photomask has a predetermined angle θ (0<θ<1 deg) relative to the linear pattern of the light transmission portion of the previous photomask.

A method for producing an elongated wired circuit board including a plurality of wires arranged in parallel, the method including the steps of:

• a first step, in which an insulating layer is prepared, and
• a second step, in which the plurality of wires arranged in parallel are formed on the surface of the insulating layer,
• wherein the second step includes
• A step (1), in which a metal thin film is formed on the surface of the insulating layer,
• a step (2), in which a photo resist is formed on the surface of the metal thin film,
• a step (3), in which a photomask is disposed on the surface of the photo resist so as to face the photo resist, and the photo resist is exposed to light through the photomask, the photomask having a shield portion formed as a plurality of linear patterns arranged in parallel so as to match the plurality of the wires,
• a step (4), in which the photo resist facing the shield portion is removed to expose the metal thin film by development,
• a step (5), in which the plurality of wires are formed on the surface of the exposed metal thin film by plating, and
• a step (6), in which the remaining photo resist and the metal thin film facing the remaining photo resist are removed,
• wherein the second step includes a step of conducting the step (3) a plurality of times so that a connection portion having a width narrower than a linear pattern is formed in each wire by shifting the photomask relative to the photo resist in the elongated direction, and
• in the each step of the plurality of steps, the photomask is disposed so that the linear pattern of the shield portion of the following photomask has a predetermined angle θ (0<θ<1 deg) relative to the linear pattern of the shield portion of the previous photomask.